Core A provides expertise and resources that are essential for successful completion of each of the Projects within this Program. Core A is housed in the Ellison Stem Cell Core (ESCC), a purpose-designed and built facility providing access to tissue culture hoods, a number of Zeiss microscopes, live cell imaging capability, and hypoxia-ready incubators. Furthermore, Core A provides access to validated reagents for the culture and maintenance of human pluripotent stem cells, minimizing experimental variability that can occur between different vendors or batches. Core A also teaches and maintains a best practices environment that minimizes deviations that can lead to contamination and culture drift. However, perhaps of greatest importance are the advantages that result from the co-localization of POI investigators within the ESCC. By aggregating researchers from different disciplines, the ESCC aggregates expertise. This allows researchers from one laboratory to immediately benefit from advances made by other laboratories, facilitates the identification of important biological differences between pluripotent lines, and fosters collaborative efforts that benefit from contributions from multiple groups; a recent example being the adoption of vector-free methods for induced pluripotent stem cell (iPSC) generation. Core A will facilitate the goals of the overall POI through the provision of core services, by placing its knowledge and resources at the disposal of POI investigators, and by developing new knowledge and capabilities. During the current funding period Core A has made important contributions toward furthering our knowledge of stem cell biology. The current application proposes to continue in this vein by characterizing a new generation of naive-like human pluripotent stem cell lines, by developing culture conditions that will enhance the predictability with which human pluripotent stem cell lines generate tissues of interest, and by seeking to identify metabolic drivers of pluripotency and directed differentiation.